This invention relates to a backing strip for a windscreen wiper blade assembly and a wiper blade clip.
The dramatic changes that have occurred in automotive and vehicular windshield/windscreen designs worldwide for improved aerodynamics and expanded visibility has created a profusion of windshield wiper refill lengths that has caused refill manufacturers to produce refills in sizes of:
8.0"; 8.2"; 8.5"; 9.0"; 9.5"; 9.75"; 10.0"; 10.25"; 10.5"; 11.0"; 11.25"; 11.5"; 12.0"; 12.5"; 12.875"; 13.0"; 13.5"; 13.875"; 14.0"; 14.25"; 14.5"; 14.875"; 15.0"; 15.5"; 15.9"; 16.0"; 16.25"; 16.5"; 16.75"; 16.875"; 17.0"; 17.5"; 18.0"; 18.25"; 18.5"; 18.75"; 18.875"; 19.0"; 19.5"; 19.875"; 20.0"; 20.5"; 21.0"21.5"; 22.0"; 22.25"; 22.5"; 23.0"; 23.5"; 24.0"; 24.25"; 24.5"; 24.875"; 25.0"; 25.5"; 26.0"; 26.875"; 27.0"; 27.9"; 28.0"; 28.5"; 32.0"; 39.0"; 40.0"; PA1 a base section for location at an end of the backing strip; PA1 a first pair of legs coupled to and extending transverse to the base section and adapted to overlie the first pair of rails of the backing strip, the first pair of legs being spaced apart by a first predetermined distance; PA1 a second pair of legs coupled to and extending transverse to the base second and being opposed to the first pair of legs, the second pair of legs being adapted to overlie the second pair of rails, the second pair of legs being spaced apart a second predetermined distance which is greater than the first predetermined distance at which the first pair of legs are spaced; PA1 abutment members on each of the first and second pair of legs; PA1 attachment means for attaching the clip to the backing strip; and PA1 wherein dependent on which of the first or second rails are engaged with the opposed claws, the first or second pair of legs which overlie that pair of rails are, in use, engaged with one pair of the opposed claws by location of the abutment members behind said one pair of opposed claws to secure the backing strip to the one pair of opposed claws to limit longitudinal movement of the backing strip relative to the opposed claws. PA1 first and second channels for alternatively receiving a wiper blade element, the backing strip having a first pair of rails which include longitudinal edges spaced apart by a first predetermined distance and a second pair of rails having longitudinal edges spaced apart by a second predetermined distance which is greater than the first predetermined distance, the backing strip being coupleable to the blade frame by engaging either the first or second pair of rails with the opposed claws dependent upon the size of the opposed claws, and by the blade element being located in the first or second channel dependent upon which of the first or second pair of rails are engaged with the opposed claws; PA1 a first clip arranged at one end of the backing strip and having a pair of legs which overlie the first pair of rails, the legs being spaced apart by a first predetermined distance; PA1 a second clip arranged at the other end of the backing strip and having a pair of legs which overlie the second pair of rails, the second pair of legs being spaced apart by a second predetermined distance which is greater than the first predetermined distance at which the first legs are spaced apart; PA1 abutment members on each of the first and second pair of legs of the first and second clips; and PA1 wherein dependent upon which of the first or second pair of rails are engaged with the opposed claws, the legs of the first or second clip which overlie that pair of rails are engageable with one of the opposed pair of claws so that the abutment members are arranged behind the said one of the pair of opposed claws to secure the backing strip to the one pair of opposed claws to limit longitudinal movement of the backing strip relative to the opposed claws. PA1 a first pair of rails having longitudinal side edges which are spaced apart by a first predetermined distance; PA1 a second pair of rails which have longitudinal edges spaced apart by a second predetermined distance; and PA1 a third pair of rails which have longitudinal side edges spaced apart by a third predetermined distance. PA1 a backing strip having at least first and second pairs of rails for engaging the opposed claws of the windscreen wiper blade assembly; PA1 a clip arranged at one end of the backing strip and having; PA1 wherein the clip is held firmly to the backing strip by the base section which prevents substantial movement of the clip relative to the backing strip in a first direction parallel to the longitudinal direction of the backing strip, the attachment tongue which prevents substantial movement of the clip away from the backing strip in a direction opposite the first direction, the first pair of legs which prevent substantial movement of the clip in a third direction perpendicular to the longitudinal direction of the backing strip, and the second pair of legs which prevent substantial movement of the clip in a fourth direction perpendicular to the longitudinal axis of the backing strip and opposite to the third direction. PA1 a first pair of legs overlying the first pair of rails of the backing strip, the first pair of legs being spaced apart by a first predetermined distance; PA1 a second pair of legs opposed to the first pair of legs, the second pair of legs overlying the second pair of rails, the second pair of legs being spaced apart a second predetermined distance which is greater than the first predetermined distance at which the first pair of legs are spaced; PA1 abutment members on each of the first and second pair of legs; PA1 attachment means for attaching the clip to the backing strip; and PA1 wherein dependent on which of the first or second rails are engaged with the opposed claws, the first or second pair of legs which overlie that pair of rails are, in use, engaged with one pair of the opposed claws by location of the abutment members behind said one pair of opposed claws to secure the backing strip to the one pair of opposed claws to limit longitudinal movement of the backing strip relative to the opposed claws.
and lengths in between and beyond and the metric equivalents of these lengths. The most common length for passenger motor vehicles, covering virtually 95% of all users, range from 8.0"to 24.0".
Manufacturers of windshield wiper blade frames or superstructures, whether from the motor vehicle original equipment industry or from the automotive aftermarket industry, have created further profusion in the manufacture of refills by producing blade frames having straddling claws of many and varied widths, with some blade frames having a fairly consistent width of claws over the length of frame and some having multiple widths of claws in the same frame. This multitude of frames require refills in widths of 3.95 mm; 4.0 mm; 4.5 mm; 4.75 mm; 4.9 mm; 5.0 mm; 5.25 mm; 5.5 mm; 6.0 mm; 6.1 mm; 6.3 mm; 6.5 mm; 7.0 mm; 8.0 mm; 8.1 mm; 8.3 mm; 8.5 mm; 9.0 mm; 9.4 mm; 9.5 mm; 10.5 mm; 10.67 mm; 11.0 mm; 11.56 mm; 11.94 mm; 12.5 mm; 13.5 mm; 14.48 mm; 14.5 mm; 15.0 mm; 15.24 mm; 16.0 mm; 17.78 mm; 18.8 mm; 20.57 mm; and widths in between and beyond and the American/Imperial equivalents of these widths. The most common widths for passenger motor vehicles, covering virtually 95% of all users, range from 6.0 mm to 13.5 mm.
All these lengths and widths have made manufacturing and stock keeping units (SKU's) particularly onerous, expensive and wasteful and has negated and impacted unfavourably on the use and application of wiper blades and refills. It has in fact caused the motorist(s) to replace their wipers less often because of confusion on the motorist's part and difficulty in choice and fit to the impairment of visibility and safety. It has also forced the motorist, in some circumstances, to purchase from the motor vehicle dealer the original equipment refill specifically made for that frame at a much higher price than an aftermarket supplier would need.
A recent survey undertaken at two international automotive parts trade shows revealed the extent of the problem:
______________________________________ Manufacturer "A" 19 Different Refills Manufacturer "B" 48 Different Refills Manufacturer "C" 20 Different Refills Manufacturer "D" 22 Different Refills ______________________________________
Some attempt to overcome the difficulty of multitudes of widths has been made by the use of a spreader that will widen metal claws to accept the available refill. A danger here is that the claws may break, making the system unsafe. Plastic frame claws cannot be widened.
Various other refills have been produced that claim to be multifit or universal. Generally, these are designed to fit only two widths, being nominal 6 mm and nominal 8 mm but not being able to fit nominal 9.5 mm wide claws, this latest width being common on later American-made vehicles. Further, widths of 12.5 mm and more for heavy duty trucks and for buses have not been catered for by existing universal refills. One universal refill has snap off rails. These may inadvertently break in operation.
One problem experienced with other multifit-type refills is that they utilise a removable, replaceable retention clip. This clip could be dropped by the motorist and lost, causing the refill to be unusable. The clip could also be improperly refitted, causing dislodgment in operation, with the danger being that the refill could slide out of the frame, causing a loss of driving vision and damage by the frame to the glass and windshield surrounds.
Certain refills incorporate a plastic retention clip. These clips tend to be easy to dislodge and, in hot weather, can deform and soften. This leads to the clip not locating on the claw, causing the refill to slide out of the claws, resulting in loss of vision and damage to the glass and windshield surrounds. Some clips only have one retention arm, thereby halving the holding strength. Some clips also have the retention arm/s locating outside the claw. These clips may become dislodged during manual cleaning of the vehicle and when the vehicle is in an automatic car wash.
Some metal clips are made from metals containing iron which, if not carefully treated, results in a rusted clip and weakness in retention. Still further metal clips have been produced across the grain of the metal instead of along the grain. These made across the grain have little spring inherent in them, do not hold sufficiently well and can deform and break in installation and operation.
Another problem experienced by other designs of multifit refills is that the space available in the internal cavity of the claws has been insufficient and has caused the uppermost unutilised rails to bind up or create so much friction and tight fit that the backing strip cannot be threaded or that, once threaded, the backing strip is now so inflexible that it will not conform to the curvature of the glass, thus giving an improper and patchy wipe. This produces an unsafe driving condition. The situation becomes exacerbated with modern vehicles with aerodynamic windshields as the wiper must also cope with up to 1000 different angles/radii during one cycle of travel over a windshield. Radii of windshields and blades have been measured at 350 mm; 430 mm; 474 mm; 500 mm; 525 mm; 583 mm; 592 mm; 600 mm; 630 mm; 632 mm; 663 mm; 665 mm; 730 mm; 750 mm; 796 mm; 800 mm; 867 mm; 956 mm; 1000 mm; 1130 mm; 1169 mm; 1300 mm; 1500 mm; 1540 mm; 1873 mm; 2000 mm; 2500 mm; and nominal infinity for nominal flat glass.
A further difficulty experienced with original equipment and aftermarket refills is the difficulty experienced, at times, with some retention methods, where coins or pliers are needed to remove the refill. As well as the inconvenience of having the implements at hand, the possibility exists of damage to the frame and the glass. Some refills must be cut whilst in the frame prior to removal. This raises the possibility of the installer being harmed.
Certain replacement refills have a backing strip made from various metals. These have the inherent danger of being sharp on the edges which are gripped by the installer in removing and replacing, leading to lacerated fingers and thumbs. Additionally, there can be a tendency for the metal of the claw becoming exposed to the metal backing strip, leading to rusting/oxidation at the point of contact.
Some refills incorporate two loose metal flexors which, when located in pockets in the squeegee, can be difficult to remove and may cause damage to the frame in the process. When installing a new refill of this type, considerable skill and patience is required to keep a firm grip on three loose components at the same time and to carefully thread these in unison along the full length of the frame.
A further problem with other types of refills is that the frames on older vehicles may have claws that have been spread over a period of time and use, necessitating the squeezing of claws to fit a narrower pair of rails. This raises the possibility of breakage. Additionally, some refill rails are too thick in the wall section to accept certain thicknesses of claw material. If an unsuitable refill is forced to fit, it becomes too rigid to adequately and flexibly wipe the glass.